Three elements combine to create a tropical garden; tall stately palms, dramatic large leaves and bright colours. Such a look is perfect for poolside planting, around ponds and city ‘jungles’.
Select tall, feather-leaved palms to provide the canopy. Suitable species include Bangalow or King palms (Archontophoenix cunninghamiana and A. alexandrae), Kentias (Howea forsteriana) Majesty palms (Ravenea rivularis) or perhaps the Senegal Date palm (Phoenix reclinata).
Now work down to smaller palms that will look just perfect at eye-level. Both Chamaedorea cataractarum (the Cascade palm) and C. microspadix (the Bamboo palm) look great in this environment. For bright spots you might consider the Pigmy Date palm (Phoenix roebelenii) or Cycas revoluta (the Sago ‘Palm’).
Another couple of palms which deserve to be much more commonly planted in such situations are the Sugarcane palm (Dypsis baronii) and the Himalayan Fishtail palm (Caryota maxima). For its unusual appearance you might also consider the Cardboard ‘Fern’ Zamia furfuracea (actually a cycad).
In addition to palms consider bushes such as Tetrapanax papyrifer (the Rice Paper Plant), Brugmansias, bright Hibiscus and perhaps Vireya Rhododendrons for darker spots.
On fences (or the trunks of older palms) you can’t beat the bright flowers of the climber Bougainvillea.
Finally under-plant with cannas for their bright colours and tropical foliage, gingers for their flowers and scent and aroids such as colocasias and alocasias for their huge leaves.